The Research On The Radiation Induced Mutation Breeding Of Elm

Ulmus Pumila Linn is one of the major native species in our province. With strong capability of resistance and less need of organization, it is widely located and has a large variety of usages. (Such as being planted along the roads, being used to resist sand, green the surroundings, etc.) It is one of the most important species that are used in gardening and also it is one of the precious native trees. Since people have not paid much attention to it, the research on it stagnates comparatively.The research project is meant to pick out the ideal species for landscaping by applying Cu radiation to elm seed in order to induce mutation.Through the pre-experiment in our lab, we identify that 50Gy is the semi-lethal dose.This experiment contains 10 degrees as followings: Group 30Gy, Group 50Gy, Group 70Gy, Group 90Gy, Group 100Gy, Group 200Gy, Group 300Gy, Group 500Gy, Group 1000Gy, Group 1 500Gy and CK. 10000 seeds are picked out as a sample unit for each degree.By comparing and observing all the groups in the field, we get the results as followings: in Groups 30-90Gy, the seeds sprout evenly; in Group 30Gy the cotyledon becomes obviously yellowing; in Group lOOGy the seeds sprout well but come out two days late and with weaker shoots than the Groups 30-90Gy; in Groups 200-500 Gy, the sprouting happens, but the shoots are severely twisted and ill and gradually die ten days later; in Groups 1000-1500Gy, no sprout at all. Within the Groups 30-100Gy, we choose consequently such 5 types of induced mutation as the followings: small-leaf type, strong ramifying type, green-reduced leaf (yellow green and gray green), season-gap shortened type and autumn color type (purple-red). At the same time we still observe the radiating injury to leaf type, growth point and we also get a chimera plant of whiten leaf and normal one.